Sales of the Nissan Leaf totaled 3,539 in the first quarter, more than double compared with last year's first quarter, but still not enough to overtake the Volt or Tesla.

In an interview, Tesla founder and chief Elon Musk had a somewhat subdued reaction to the sales figures, saying he didn't care much about leading the sales charts.

"My goal in creating Tesla was to accelerate the use of electric cars," Musk said.

"It's unfortunate there are not more sales of other electric cars," he added. "We need to increase electric car sales to bring sustainable transport closer, but I don't mind if anyone sells more of them than us."

In fact, Musk didn't even mention the sales figures in a Friday morning teleconference that was devoted to the company's performance in servicing Tesla customers.

Musk, looking to allay fears about the durability of electric car batteries, is guaranteeing that all battery problems in his cars will be covered unless the owner did something deliberate to the battery, like taking a blowtorch to it.

He said that his company's batteries would be covered even if the owner had not followed charging guidelines issued in the vehicle owners manual.

"This is all to address customer concerns. 'What if my battery dies?'" Musk said "We want to say, 'Don't worry about it.' As long as the damage is not deliberate, we'll cover it."

Talking about his company's performance in general, Musk said Tesla customer car service was "good, but not great. It has to be great."

Eric Lyman, vice president for editorial for ALG, said the battery promise "seems like another great way to reassure the customer." Among other things, ALG forecasts automotive residual values.

Musk also said that he would provide brand new, fully loaded Model S sedans as loaner cars if an owner had to leave his vehicle for extended service or repairs.

Musk also raised some eyebrows when he said the owner could keep the loaner if he liked it better than his own car, just having to pay the difference in the value of the two cars.

"Everything he seems to do flies against what is happening in the rest of the auto industry," Lyman said. "He is going to have some misses, but he is going to hit home runs too."